Imagine you lived in Barcelona and lost your job, like thousands of Spaniards did each year of the most recent recession. And also, imagine you were pregnant. Would you sit around the house, anxiously sending out job applications and stress-snacking on churros? Or would you take long walks in the Mediterranean sun and stop at farmers' markets along the way?

Spanish moms, it seems, often choose the latter.

Libertad González, an associate professor at the Universitat Pompeu Fabra, recently examined the health of registered newborns in Spain from 1981 to 2010, and she cross-referenced the data with the unemployment rate in each of the country's provinces at the time. With each 10 percent increase in unemployment, she found, the neonatal death rate dropped by 7 percent, and the percent of babies with low birth weights decreased by 3 percent.

Institute for the Study of Labor

The reason? During recessions, mothers consistently reported being in better health, and they exhibited healthier behaviors: “They smoke and drink less, exercise and sleep more, and weigh less,” Gonzalez wrote.

Her findings mesh with past research in the U.S. showing that health improves during periods of low economic growth. A 2004 study of American babies, for example, also found that those born in periods of high unemployment had fewer birth defects, were more likely to weigh a healthy amount, and were less likely to die.

Research by Chris Ruhm, a public policy professor at the University of Virginia, has shown that people tend to exercise less during economic upswings, and they tend to eat out more—and restaurant meals are usually higher in fat and calories. In Cuba, for example, a period of pronounced, years-long austerity led to a steep drop in obesity and cardiovascular disease because people walked and biked more as public transportation was scaled back.

People who work less also have more time on their hands, so they sleep more and feel less stressed, Ruhm said. And there are fewer cars on the roads, so the air is cleaner and there are fewer car accidents.

Mortality rate and unemployment rate over time (Ruhm/Massachusetts Institute of Technology Press)

“Interestingly, there’s evidence that short-term reductions in income are actually good for you,” he told me.

But how could this be? Wouldn't job loss also cause people to scale back on gym memberships and kale salads? Well, yes. And this is one of those counterintuitive trends that becomes more intuitive once you hear all the caveats.

“When times are bad, people are healthier but not happier."

These studies evaluate overall unemployment and GDP, not job loss at the individual level. That is to say, they only suggest that health improves as the economy overall slows down. So, much of this might have to do with hourly employees working less overtime and spending more of their free time on cooking and jogging. Or it could be that families are feeling pinched and eating out less, rather than becoming totally destitute.

The key here are temporary dips in income. Long-term unemployment, which has skyrocketed in Spain and other parts of Europe, is still terrible for mental and physical health. In fact, it could be that we'll see the reverse of the Spanish results playing out if the women aren't able to return to the workforce and provide stable homes for their kids.

There also might be some self-selection going on. People generally have fewer babies during recessions, so the couples who do procreate in lean times might already be comfortable enough to ensure that their offspring flourish, no matter what. (This factor didn’t explain the healthier babies in the Spanish sample, however.)

And since there are fewer babies being born, it could be that hospitals—especially publicly funded ones like Spain’s—are less busy during economic slumps and can provide better care for each baby as a result.

There’s also one very important downside to recessions—a gradual deterioration in mental health, and an attendant rise in suicides. “When times are bad, people are healthier but not happier,” Ruhm said.

So it could be that this and similar studies are not really an argument for pregnant women to leave the workforce, but simply to scale back their hours. Or to keep their jobs the same, but to live life more like a marginally employed Spanish woman—sleeping enough, walking a lot, and slurping up plenty of gazpacho.